IBM Breakthrough Advances Nanotechnology Research

By Jeffrey Burt |
Posted 2010-09-23

IBM Breakthrough Advances Nanotechnology Research

As the computer industry continues chasing Moore's
Law and components continue to shrink, the march continues to the inevitable
end point: the atom. IBM researchers say
they now have made a significant breakthrough that brings the industry a step
closer to that end point.

In an article that will be published Sept. 24 in Science
magazine, IBM researchers are outlining a
new technique that can measure how long a single atom can hold data, and that enables
scientists to record, study and visualize the magnetism of these atoms at
extremely fast speeds.

Using IBM's STM
(Scanning Tunneling Microscope) in a fashion similar to a high-speed camera,
researchers at IBM Research's Almaden Lab
can study the behavior of atoms at a speed 1 million times faster than before.

This ability to record and study atom behavior at nanosecond
speeds opens up several avenues of research for the scientists because they now
can add time as a dimension in their experiments. The results of all this could
impact everything from solar cells to quantum computing to nanoscale data
storage capabilities.

"If you take Moore's Law to the end, where you end up at
is the atom," Andreas Heinrich, IBM
Research staff member and group leader of nanoscale science at the Almaden Lab,
said in an interview with eWEEK, adding that the question then becomes, Can you
do computing and other work at that scale? "If you can do this, you reach ...
not only for IBM, but for the entire
industry, the holy grail."

IBM scientists have been
using the STM for two decades to study
matter at the atomic scale, which Big Blue officials said could lead to
innovations around computing and data storage. With the new technique using the
STM, researchers can study the behavior of
atoms at the nanosecond level, whereas before it was at the millisecond level,
Heinrich said.

That's important, according to IBM.
The difference between a nanosecond and a second is equivalent to the
difference between a second and 30 years, according to company officials. Now,
because of the new technique, scientists can see the physics that happens
during that time that they couldn't have seen before.

"What this breakthrough is really about is [moving from]
milliseconds to nanoseconds," Heinrich said.

"This technique developed by the IBM
Research team is a very important new capability for characterizing small
structures and understanding what is happening at fast time scales,"
Michael Crommie, professor of physics at the University
of California Berkeley and a
faculty researcher at the Lawrence Berkeley National Labs, said in a statement.
"I am particularly excited by the possibility of generalizing it to other
systems, such as photovoltaics, where a combination of high spatial and time
resolution will help us to better understand various nanoscale processes important
for solar energy, including light absorption and separation of charge."

Previously, scientists had determined that an iron atom could
hold data for a nanosecond. Now, with the new STM
technique, they found that when putting a non-magnetic copper atom next to the
iron atom, that iron atom could retain data for up to 200 nanoseconds. Being
able to see that change means that scientists can now experiment to see how
they can impact the behavior of atoms to get desired results.

According to IBM, the breakthrough
could impact quantum computers, which are systems that aren't bound by the
binary nature of traditional computers. Gaining a greater understanding of the
nature of atoms could lead to researchers being able to perform advanced
computations that currently aren't possible.

Can Information Be Stored on a Single Atom?

In the data storage arena, now that scientist can essentially
see an atom's electronic and magnetic properties, they can study whether
information can reliability be stored on a single atom.

IBM scientists were able to
develop a new technique for the STM that
enabled it to record the behavior of atoms stroboscopically, similar to how the
first movies were created or to time-lapse photography. This was needed because
the magnetic spin of an atom changes too fast to measure directly using the STM,
according to the company.

Researchers use a "pump-probe" measurement technique,
where a fast voltage pulse excites the atom. Then a weaker voltage pulse
measures the nature of the atom's magnetism at a certain time after the
excitation. The time delay between the two pulses creates a time frame of each
measurement. The delay is then varied, and the average magnetic motion is
recorded in small time increments. Taken together, the recorded increments give
the scientists a more complete picture of the magnetic motion of the atom,
similar to how a series of incremental photos can create a motion picture.

For each time increment, the alternating pulses are repeated
about 100,000 times, which takes less than a second.

IBM scientists used iron
atoms that were put onto an insulating layer one atom thick and supported on a
copper crystal and position next to non-magnetic copper atoms. The structure
was then measured when in the presence of different magnetic fields, which
showed that the speed at which they changed their magnetic orientation depends
on the magnetic field. Essentially, the scientists found that the atom's
magnetism can reverse direction without having to go through intermediate
orientations.

Knowing this, researchers may be able to engineer the magnetic
lifetime of the atoms to make them longer-to retain their magnetic state-or
shorter-to switch to new magnetic states-as needed.

"This breakthrough allows us-for the first time-to
understand how long information can be stored in an individual atom, Sebastian
Loth, at IBM Research, said in a statement. "Beyond
this, the technique has great potential because it is applicable to many types
of physics happening on the nanoscale."

IBM Research's Heinrich said
it is far too early to tell if or how this will result in productized
technologies. It will probably take another two to five years to determine
whether atoms can be manipulated to store data for hours or days, rather than
nanoseconds, and even longer-15 years or more-to determine whether any of this
research will result in products. Finding that out is the goal, he said.

"Jumping to the scale of a single atom, that is clearly at the end of
the road map," Heinrich said.